This invention relates generally to control systems and more specifically to industrial control systems that use embedded programs as a part of an industrial control system.
Known electronic systems are extensively used in process control applications. These electronic systems are usually modular, that is, a central processing unit (CPU) communicates with a series of replaceable modules, sometimes called input/output (I/O) modules that are connected to the CPU in a bus arrangement. I/O modules are configured with a common interface to the electronic system. In addition, specific input/output circuitry is contained within a particular I/O module depending on the function performed (i.e. the specific input/output requirements of a particular industrial control application). In one aspect of industrial control, the CPU monitors inputs and outputs from various I/O modules.
Typical electronic systems, such as those used in industrial control applications execute a plurality of program blocks, as part of an integrated control system. A typical integrated control system contains multiple modules used to control various hardware interfaces. One problem with electronic systems of this type is that when it is necessary to update a program block, the electronic system has to be stopped, even though the program block to be updated is not executing. Stopping the electronic system also means that the process being controlled, an assembly line for example, has to be stopped.
It would therefore be desirable to provide a method where program blocks can be updated without stopping execution of other program blocks within the electronic system or the stopping of the entire electronic system.
In an exemplary embodiment of the invention, a method of implementing program updates in an electronic system is described. The method includes requesting the system to accept a program update and loading replacement programs for execution.